Re: [PATCH vhost 08/23] vdpa/mlx5: Clear and reinitialize software VQ data on reset

From: Eugenio Perez Martin
Date: Wed Jun 19 2024 - 07:28:56 EST


On Mon, Jun 17, 2024 at 5:08 PM Dragos Tatulea <dtatulea@xxxxxxxxxx> wrote:
>
> The hardware VQ configuration is mirrored by data in struct
> mlx5_vdpa_virtqueue . Instead of clearing just a few fields at reset,
> fully clear the struct and initialize with the appropriate default
> values.
>
> As clear_vqs_ready() is used only during reset, get rid of it.
>
> Signed-off-by: Dragos Tatulea <dtatulea@xxxxxxxxxx>
> Reviewed-by: Cosmin Ratiu <cratiu@xxxxxxxxxx>

Acked-by: Eugenio Pérez <eperezma@xxxxxxxxxx>

> ---
> drivers/vdpa/mlx5/net/mlx5_vnet.c | 16 +++-------------
> 1 file changed, 3 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index c8b5c87f001d..de013b5a2815 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -2941,18 +2941,6 @@ static void teardown_vq_resources(struct mlx5_vdpa_net *ndev)
> ndev->setup = false;
> }
>
> -static void clear_vqs_ready(struct mlx5_vdpa_net *ndev)
> -{
> - int i;
> -
> - for (i = 0; i < ndev->mvdev.max_vqs; i++) {
> - ndev->vqs[i].ready = false;
> - ndev->vqs[i].modified_fields = 0;
> - }
> -
> - ndev->mvdev.cvq.ready = false;
> -}
> -
> static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev)
> {
> struct mlx5_control_vq *cvq = &mvdev->cvq;
> @@ -3035,12 +3023,14 @@ static int mlx5_vdpa_compat_reset(struct vdpa_device *vdev, u32 flags)
> down_write(&ndev->reslock);
> unregister_link_notifier(ndev);
> teardown_vq_resources(ndev);
> - clear_vqs_ready(ndev);
> + init_mvqs(ndev);

Nitpick / suggestion if you have to send a v2. The init_mvqs function
name sounds like it can allocate stuff that needs to be released to
me. But I'm very bad at naming :). Maybe something like
"mvqs_set_defaults" or similar?

> +
> if (flags & VDPA_RESET_F_CLEAN_MAP)
> mlx5_vdpa_destroy_mr_resources(&ndev->mvdev);
> ndev->mvdev.status = 0;
> ndev->mvdev.suspended = false;
> ndev->cur_num_vqs = MLX5V_DEFAULT_VQ_COUNT;
> + ndev->mvdev.cvq.ready = false;
> ndev->mvdev.cvq.received_desc = 0;
> ndev->mvdev.cvq.completed_desc = 0;
> memset(ndev->event_cbs, 0, sizeof(*ndev->event_cbs) * (mvdev->max_vqs + 1));
>
> --
> 2.45.1
>